Dual balloon fluid endometrial treatment of uterine tissue

Abstract

A medical device includes: a shaft having a distal end and an associated exhaust channel; a first balloon configured to be attached to the distal end of the shaft, the first balloon having an outer surface that is substantially conformal to an inner surface of a uterine cavity; and a second balloon configured to be received within the first balloon and forming an intermediary space between the first balloon and an outer surface of the second balloon. The second balloon includes at least one rupture valve configured to rupture at a predefined pressure in the intermediary space.

What is claimed is: 
     
       1. A method comprising:
 providing or obtaining a medical device comprising a first balloon, a second balloon arranged within the first balloon and having at least one rupture valve, and a fluid-tight intermediary space between the first balloon and the second balloon; 
 wherein the at least one rupture valve is configured to rupture in response to at least a predefined pressure being applied to an outer surface of the second balloon; 
 inserting the medical device into a uterine cavity; 
 providing an agent into the fluid-tight intermediary space; 
 inflating the fluid-tight intermediary space with the agent to cause the first balloon to conform to a shape of the uterine cavity; and 
 exhausting the agent through the at least one rupture valve and out of the second balloon. 
 
     
     
       2. The method of  claim 1 , further comprising balancing a pressure of the agent while inflating the fluid-tight intermediary space and while exhausting the agent through the at least one rupture valve and out of the second balloon. 
     
     
       3. The method of  claim 2 , wherein balancing a pressure of the agent while inflating the fluid-tight intermediary space and while exhausting the agent through the at least one rupture valve and out of the second balloon comprises using a pressure balance valve. 
     
     
       4. The method of  claim 1 , wherein exhausting the agent through the at least one rupture valve and out of the second balloon comprises causing a pressure in the fluid-tight intermediary space to exceed a predefined pressure calculated to maintain a structural integrity of the at least one rupture valve. 
     
     
       5. The method of  claim 1 , wherein providing the agent into the fluid-tight intermediary space comprises introducing nitrous oxide into the fluid-tight intermediary space. 
     
     
       6. The method of  claim 1 , wherein inflating the fluid-tight intermediary space with the agent to conform to a shape of the uterine cavity comprises lowering a temperature at an outer surface of the first balloon to about −20 degrees C. 
     
     
       7. The method of  claim 1 , wherein inflating the fluid-tight intermediary space with the agent to cause the first balloon to conform to a shape of the uterine cavity ablates uterine tissue at an inner wall of the uterine cavity. 
     
     
       8. The method of  claim 1 , wherein the at least one rupture valve is offset from a mouth of the second balloon. 
     
     
       9. The method of  claim 1 , wherein the agent comprises a fluid medium. 
     
     
       10. The method of  claim 9 , wherein the fluid medium comprises a gaseous medium. 
     
     
       11. A method of performing endometrial ablation, the method comprising:
 providing or obtaining a medical device comprising a shaft having a distal end, a first balloon configured to be attached to the distal end of the shaft, a second balloon configured to be received within the first balloon such that an intermediary space is defined between the first balloon and the second balloon; 
 inserting the medical device into a uterine cavity; 
 providing a gaseous medium into the intermediary space; 
 cycling the gaseous medium through the intermediary space and through a rupture valve into the second balloon; and 
 ablating uterine tissue at an inner wall of the uterine cavity using an outer surface of the first balloon. 
 
     
     
       12. The method of performing endometrial ablation as in  claim 11 , wherein providing a gaseous medium comprises introducing nitrous oxide gas into the intermediary space between the first balloon and the second balloon. 
     
     
       13. The method of performing endometrial ablation as in  claim 11 , wherein cycling the gaseous medium through the intermediary space and the second balloon comprises pressurizing the intermediary space between the first balloon and the second balloon, causing a rupture valve in the second balloon to rupture, and exhausting the gaseous medium from the second balloon. 
     
     
       14. The method of performing endometrial ablation as in  claim 13 , wherein pressurizing the intermediary space, causing a rupture valve to rupture, and exhausting the gaseous medium comprises balancing a pressure into the first balloon with a pressure out of the second balloon using a pressure balance valve. 
     
     
       15. The method of performing endometrial ablation as in  claim 11 , wherein ablating uterine tissue at an inner wall of the uterine cavity using an outer surface of the first balloon comprises maintaining the outer surface of the first balloon on the inner wall of the uterine cavity for at least one of a predetermined amount of time and a predetermined temperature. 
     
     
       16. The method of performing endometrial ablation as in  claim 11 , wherein ablating uterine tissue at an inner wall of the uterine cavity using an outer surface of the first balloon comprises lowering a temperature of the outer surface of the first balloon to about −20 degrees C. 
     
     
       17. The method of performing endometrial ablation as in  claim 8 , wherein ablating uterine tissue at an inner wall of the uterine cavity using an outer surface of the first balloon is used to treat menorrhagia. 
     
     
       18. A medical device comprising:
 a shaft having a distal end and an associated exhaust channel; 
 a first balloon configured to be attached to the distal end of the shaft, the first balloon having an outer surface that is substantially conformal to an inner surface of a uterine cavity; 
 a second balloon configured to be received within the first balloon and forming an intermediary space between the first balloon and an outer surface of the second balloon; 
 wherein the second balloon includes at least one rupture valve configured to rupture at a predefined pressure in the intermediary space establishing an intake port to a volume within the second balloon; and 
 an exhaust port configured to allow an exhaust flow to pass from the intake port to the associated exhaust channel via the volume within the second balloon. 
 
     
     
       19. The medical device of  claim 18 , wherein the at least one rupture valve comprises a flap having at least one edge that is integrally formed with a surface of the second balloon and at least one edge that is configured to rupture at a predefined pressure. 
     
     
       20. The medical device of  claim 18 , wherein the at least one rupture valve comprises a slit defined by a structurally weakened elongated closure. 
     
     
       21. The medical device of  claim 18 , wherein the at least one rupture valve comprises a hole having a covering removably adhered to an outward-facing surface of the second balloon and covering the hole. 
     
     
       22. The medical device of  claim 18 , wherein the at least one rupture valve is offset from a mouth of the second balloon.